Hepatic Fas protein expression might be a predictive factor for hepatocellular carcinoma development in patients with chronic hepatitis C undergoing interferon therapy

BACKGROUND: Several studies have revealed that interferon treatment may reduce the incidence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C virus (HCV). However, even after eradication of HCV, patients remain at risk for developing HCC. STUDY: Of 153 consecutive HCV patients who were treated with interferon and followed up for 5 years, 17 (11.1%) developed HCC. To elucidate predictive factors of HCC development, multivariate analysis was done for the 153 patients, and Fas protein expression in the biopsied specimens of liver before interferon treatment was examined in 17 patients who developed HCC and 17 patients who did not. RESULTS: Among the independent factors (sex, age, HCV genotype, HCV-RNA level, effect of interferon therapy, serum alanine aminotransferase before interferon therapy, and histologic stage and grade) tested by Cox proportional-hazards analysis, histologic stage (hepatic fibrosis) before interferon was significantly associated with HCC development (p = 0.01). In addition, the intensity of Fas protein expression was significantly greater in the liver specimens of the patients who developed HCC than in those who did not (p = 0.015). CONCLUSION: Histologic stage (hepatic fibrosis) and Fas protein expression before interferon treatment might be indicative of the need for intensive follow-up in patients with chronic hepatitis C undergoing interferon therapy.     

Biochemical and morphological effects of bladder pumping on the urinary bladder in rats

AIMS: To study the influence of bladder pumping on the urinary bladder in 44 female rats. METHODS: Under halothane anesthesia, a urethral catheter was inserted into the bladder of 27 rats, and air (0.4-0.8 mL) was pumped in and out of the bladder at 0.5 cycles/second for a period of 5 minutes. Twenty-four hours after pumping, the bladder was harvested for measurement of the tissue levels of myosin, actin, and nerve growth factor, as well as for electron microscopy. In nine of the 27 rats, cystometry was performed without anesthesia before and 1, 7, 30, and 90 days after bladder pumping. The remaining 17 rats that did not undergo pumping were anesthetized and their bladders were harvested as a control. RESULTS: Bladder pumping increased the bladder capacity and decreased the maximum bladder contraction pressure, but did not increase the residual volume. Bladder pumping also increased the tissue level of nerve growth factor and decreased the levels of myosin and actin. Electron microscopy showed degeneration of bladder smooth muscle cells and nerve fibers after bladder pumping, as well as derangement and disruption of collagen fiber bundles in the bladder wall. These functional and morphological effects of pumping disappeared within 90 days. CONCLUSIONS: Bladder pumping therapy appears to have various effects on the bladder wall collagen fiber bundles, smooth muscle cells, and nerves.     

Lysophosphatidic acid induces focal adhesion assembly through Rho/Rho-associated kinase pathway in human ovarian cancer cells

OBJECTIVE: The level of lysophosphatidic acid (LPA) is elevated in patients with ovarian cancer, and LPA has been reported to have a pivotal role in cancer dissemination. In the current study, the effect of LPA on the motility of ovarian cancer cells was investigated. METHODS: We analyzed the effects of LPA on the migration activity, the focal adhesion formation, and the tyrosine phosphorylation of focal adhesion proteins in human ovarian cancer cell lines Caov-3 and OVCAR-3. Inhibitors of the small GTPase Rho, one of its downstream effectors (Rho-associated kinase (ROCK)), myosin light chain kinase (MLCK), and myosin light chain (MLC) phosphatase were used to examine the mechanism of LPA-induced cellular effects. RESULTS: LPA enhanced the migration of ovarian cancer cells and facilitated their invasion. Rho and ROCK played essential roles in the migratory process, as evidenced by the inhibition of migration and focal adhesion formation of cancer cells by Clostridium botulinum C3 exoenzyme (C3), an inhibitor of Rho, or Y-27632, an inhibitor of ROCK. LPA also evoked the formation of focal adhesions and tyrosine phosphorylation of focal adhesion kinase and paxillin, all of which were inhibited by C3 or Y-27632. CONCLUSION: These results suggest that LPA induced the migration of ovarian cancer cells, at least in part, through accelerated formation of focal adhesions mediated by Rho/ROCK-induced actomyosin contractility. This study may provide the basis for new therapies to control the metastasis of ovarian cancer.     

Fluctuation in therapeutic control associated with interchange of prednisolone tablet formulations: assessment of bioequivalence by dissolution test

A 47-year-old woman received combination therapy with prednisolone (PSL), danazol, cepharanthin, ascorbic acid, and cimetidine for the treatment of idiopathic thrombocytopenic purpura. The platelet count was well controlled for over 1 year. Then the PSL tablet formulation was altered from Tablet A to Tablet B with the same treatment regimen, but the platelet counts fell drastically thereafter. However, the platelet counts recovered by changing the PSL tablet formulation back from Tablet B to Tablet A. In vitro dissolution testing was undertaken to assess bioequivalence between Tablet A and Tablet B. PSL in Tablet B was released more slowly compared with that in Tablet A regardless of the medium pH conditions, and the difference in the release rate between the two tablet formulations increased with increasing medium pH value. The difference exceeded the allowance limit (15%) for judgment of bioequivalence under conditions above pH 4, indicating that Tablet A and Tablet B might be nonbioequivalent. The intragastric pH of the patient was probably raised due to coadministration of cimetidine. Therefore the present results suggest that the disparity in the immunosuppressive effects between the two PSL tablet formulations was attributable to the difference in their dissolution behavior in the gastrointestinal tract. We consider that it is better to avoid interchanging PSL tablet formulations in clinical practice.     

Effect of a conserved mutation in uridine diphosphate glucuronosyltransferase 1A1 and 1A6 on glucuronidation of a metabolite of flutamide

OBJECTIVE: We investigated how the conserved mutation (Y486D) changed the kinetic parameters of uridine diphosphate glucuronosyltransferase 1A1 and 1A6 (UGT1A1 and 1A6) for 2-amino-5-nitro-4-trifluoromethylphenol, which is a major metabolite of flutamide, a nonsteroidal antiandrogenic agent. METHODS: The wild-type or mutant cDNA-expressed UGT was co-incubated with 2-amino-5-nitro-4-trifluoromethylphenol (aglycone) and uridine diphosphate-glucuronic acid (UDP-GA, donor substrate). The glucuronidation of the aglycone was determined. RESULTS: The maximum velocities of the mutant UGT1A1 and UGT1A6 were about 12% and less than 1% of the corresponding wild-type, respectively. The Michaelis constant (K(M)) for the aglycone of the wild-type UGT1A1 was double that of the mutant, but the K(M) for UDP-GA of the wild-type UGT1A1 was not significantly different from that of the mutant. CONCLUSION: Patients with Y486D may accumulate excessive 2-amino-5-nitro-4-trifluoromethylphenol, which might lead to unexpected toxicity.     

Interpretation of reverse redistribution of <Superscript>99m</Superscript>Tc-tetrofosmin in patients with acute myocardial infarction

Reverse redistribution (RR) of technetium-99m tetrofosmin (TF) in patients with acute myocardial infarction (AMI) has been considered a sign of salvaged myocardium. We examined the time evolution of the RR pattern during a 6-month period and the clinical implications of RR. TF myocardial SPET was performed in 22 patients 1 week, 1 month and 3-6 months after AMI. Myocardial images were obtained 30 min and 180 min after the injection of TF. Regional uptake of TF was rated using a four-point scoring system. RR was defined as an increase of more than 1 point in the regional score on images obtained at 180 min. Echocardiography was performed to assess regional wall motion at the same time as TF imaging. RR observed at 1 week tended to disappear after 1 month and 3-6 months. The incidence of regional wall motion abnormality was reduced in patients with RR compared with that in patients with fixed defects. Recovery of abnormal regional wall motion occurred earlier in segments with disappearance of RR than in those without disappearance of RR. It is concluded that RR may reflect salvaged myocardium and that disappearance of RR may indicate earlier recovery of salvaged myocardium.     

Analysis of immune response to tumor specific antigen restricted to HLA class II on renal cell carcinoma and its recognition mechanism

PURPOSE: In this study, we studied the immune response against to human renal cell carcinoma and its antigensity. METHODS: Mixed lymphocyte tumor culture test was performed using tumor cells as stimulator cells, peripheral blood lymphocytes from tumor patient (autologous) or healthy volunteer (allogeneic) as responder cells, and tumor cells or peripheral blood lymphocytes from tumor patient as target cells. The cytotoxic activity of mixed lymphocyte tumor culture test was assayed by 51Cr-relase test, and cell surface antigens presented on tumor cells or peripheral blood lymphocytes were assayed by antibody block test. RESULTS: The cytotoxic activity against to tumor cells was induced from allogeneic peripheral blood lymphocytes by mixed lymphocyte tumor culture test. Its cytotoxic activity was inhibited by anti-CD8 antibody treatment of peripheral blood lymphocytes and anti-HLA class II antibody treatment of tumor cells. Furthermore, allogeneic peripheral blood lymphocytes induced to tumor cells did not damage peripheral blood lymphocyte of the tumor patient derivation. CONCLUSION: Renal cell carcinoma may express tumor specific antigen restricted to HLA class II antigens that could be recognized by allogeneic CD8 positive T lymphocytes.